COMPRESS                                                                COMPRESS


NAME
     compress, uncompress, zcat--file compression utility

SYNOPSIS
     compress [-dhHfvcV] [-b maxbits] [file ...]

DESCRIPTION
     Compress is a file compression utility like (and completely compatible
     with) the UNIX compress(1) program.  It can be used to compress files by
     name, or from standard input to standard output.  As UNIX-style pipes are
     not available on the Amiga, the latter capability is of dubious value, but
     is included for the sake of completeness.  Compress is able to function
     with any output code maximum size from 12 bits to 16 bits.  The higher the
     maximum code size, the more efficient the compression, and the smaller the
     resultant file, but higher sizes require more memory (e. g.:  16 bits
     uses approximately 450K of RAM, most of which must be contiguous).  For
     systems with 1 Meg or less, 13 bits is the most useful for common use.
     For systems with 1.5 Meg to 2.5 Meg, 15 bits is practical.  The bitsize
     can be selected in several ways:  the -b command line option (more on this
     below), a Manx-style environment variable, or the compiled-in default of
     13 bits.

     The environment variable, named COMPBITS, must have a value between 12 and
     16, inclusive.  It can be created using the "set" command supplied with
     the Manx Aztec C compiler (for those who have it) or a variety of public-
     domain commands that do the same thing.

     Compress will take its input list of file names and, after compression,
     deposit the compressed date in a file of the same name with a ".Z" appended
     to the end of the file name.  Thus, input file names are limited to 28
     characters (to leave room for the terminating ".Z") due to the AmigaDOS
     file name length limit.

     Compress is a completely self-contained program, in that it can uncompress
     any file it compressed.  Decompression can be done by either using the -d
     command line option or by naming the binary "uncompress" (the program
     checks the value of argv[0]).  Files can be catenated to standard output
     by the use of the -c option or by naming the binary "zcat" (this property
     is most useful when file links are available).

     Compress will accept the following command line options:

          -d:  toggle decompression (uncompress) mode,
          -h:  usage diagnostic,
          -H:  more detailed help,
          -f:  force output to file regardless of conditions,
          -v:  toggle verbose mode on,
          -c:  toggle catenation (zcat) mode,
          -V:  print version,
          -b:  select maximum bit size.


SEE ALSO
     arc, zoo.

DIAGNOSTICS
     Prints help information with -h or -H options, prints message if one of
     its calls to malloc() fails, prints a message if asked to uncompress a
     file compressed with a higher bit size than it is currently using, and
     prints messages concerning any problems with file names (file names are
     limited to 28 characters, to leave room for the terminating ".Z").  Error
     messages are generally unambiguous and informative, though the message
     returned when one of the calls to malloc() fails are somewhat whimsical.

BUGS
     None known.  Please direct any questions, comments, or bug reports to:

     Brent Woods
     320 Brown St., #406
     West Lafayette, IN  47906

     Phone:  (317) 743-8421